Vania



E. J. HOUSTON '& E. THOMSON.

DYNAMO ELECTRIC MACHINE.

Ila-296,569. Patented Apr. 1884.

' INVENTD RS M Mia. I

ATTEST: 2? M K, 0

N4 PETE UNITED STATES PATENT OriucE.

EDWIN J. HOUSTON AND ELIHU THOMSON, OF PHILADELPHIA, PENNSYL- VANIA, ASSIGNORS TO THE THOMSON-HOUSTON ELECTRIC COMPANY.

DYNAMO-ELECTRIC MACHINE.

SPECIFICATION forming part of Letters Patent No. 296,569, dated April 8, 1884.

Application filed November 30, 1878.

is, a greater numberof armature coils or bobbins, so that the reversal of current shall take place successively and not simultaneously in all of said bobbins, one-half of the terminals of said coils or bobbins being connected together or to a common conductor, while the remaining ends, are separately connected to the separate segments or plates of a commutator, to which are applied the positive and negative collectors of the machine.

Figure 1 shows in end and side view the commutator and a common collecting ring or disk for electrically uniting one-half of the terminals. Fig. 2 illustrates the relation of the armature-coil terminals to the field-of-force poles, and shows the manner in which the parts are connected. Fig. 3 shows the mannor of constructing a commutator-brush to allow for wear.

Fig. 1 shows an armature adapted to eight separate coils or bobbins, A B O D E F G H, being the separate commutator plates or segments suitably mounted upon the shaft X. R indicates a metallic ring or disk, also mounted upon the shaft, to which disk one end of each armature-coil of the set or series used in connection with the commutator is connected. The two ends of the various armature-coils are indicated by the letters a a b b, &c., the same endsfor instance, the outer ends of the coils or bobbinsbeing distinguished by the primemark. Thus, supposing that there are eightcoils or bobbins used with the commutator,

there will be sixteen terminals, two, as a a or b b, 850., from each coil, as indicated in Fig. 2. When two field-magnet poles act to induce currents in the armature-coils, as there indicated, said currents are induced successively, as one coil after another passes the poles, and the armature-coil terminals will re verse their polarity at each semi-revolution.

If the machine be so constructed that the coils reverse their polarity on'the line 00 as, all the terminals, as a b h, above that line that are connected to the commutator-plates will be of one polarity, and all similar terminals, as cl e f, below that line that are connected to the commutator-plates will be of the opposite polarity; but as there are more armature coils or bobbins than field-of-force poles, the reversal does not take place simultaneously in all. The terminals to b h will, if the armature is symmetrically made up, be simultaneously of the opposite in polarity to the terminals or b h, and similarly the terminals (1 e f will be opposite to d e f. Taking, then, all the terminals of the four bobbins on the same side of the line X X that are the same moment positive, and all those terminals of the four bobbins on the opposite side that are at the same time negative, we connect them together by joining them to the common ring or plate, It. The remaining terminals are joined seriatz'm and separately to the commutatonplates, following the same order as that belonging to the coils or bobbins in passing through the magnetic field.

In Fig. 2, Z indicates in outline the armature structure upon which the bobbins or coils are wound or supported in any of the usual ways.

The collecting-brushes P N consist of pairs of springs, 1 1, 22, 3 3, the two springs of each pair bearing on diametrically-opposite plates, while the three upon the same side of commutator are joined together to make a compound brush, which, as will be readily seen, collects the current simultaneously from those coilterminals which are for the time being of the same polarity. If desired, four pairs of springs might be used, so as to include all the eight coils. By joining the brushes P N through a working-resistance, R, the currents from the bobbins which are at the same time of opposite polarity are utilized for tension, while at the same time, owing to the fact that the reversals do not take place in all the bobbins at once, but only in succession, the current will be very uniform.

WVe do not restrict ourselves to any particular number of bobbins or coils, as it is obvious that the same results and the same principle of operation might be attained by using a larger or a smaller number than the number herein shown. If a smaller number were used, however, there would be theoretically less uniformity in current. although the same advantages in kind would result from the plurality of bobbins as compared with the number of field-poles to which said bobbins are simulis supported a lever or spring, L, a free end of which rests upon M in such manner that by means of a screw, T, the pressure of M upon the commutator-eylinder may be increased or diminished. A strip of flexible metal, as copper, S, is placed under the spring M, one extremity of the same resting in contact with the cylinder. As this extremity wears away, the strip S is pushed forward, while the spring M is protected from wear. V shows a coiled length of the strip S. I

\Ve apply our invention to any form of dynamoelectric machine having on its armature one or more series of coils or one or more series of terminals taken from the same coil, said terminals being of various polarity at the same moment, as described.

\Vhat we claim as our invention is I. In a dynamo-electric machine, the combination, with two field-poles of opposite polarity, of a plurality of armature.bobbins or coils simultaneously exposed to the inducing action of said poles, half of the terminals of l which bobbins are-joined together or to a common conductor, while the remaining terminals are connected to separate segments of a commutator.

2. The combination, with two diametricallyopposite inducing-poles in a dynamo-electric machine, of a plurality of armature coils or bobbins, the similar ends of which coils are joined separately to the separate plates of a commutator, while their opposite ends are united in a common electrical joint or connection, and two collcctingbrushes or sets of brushes applied to said commutator, and forming, respectively, the positive and the negative collector of the machine.

3. The combination, in a dynamo-electric machine, of two diametrically-opposite fieldof-i'orce poles, a plurality of armaturecoil terminals joined scriatim to the plates of a commutator, a common joint or connection for the opposite terminals ofthe coils, and apositive and negative collector applied to said commutator, and each arranged to collect the current in multiple are from those terminals which are for the time being on the same side of the shaft and are of the same polarity.

4. In a commutator for a dynamoelectric machine, the combination of an adjustable plate or spring, M, and a flexible band or strip, S, of conducting material, substantially as described.

EDW'IN J. HOUSTON. ELIHU THOMSON.

\Vitnesses:

HENRY LEFFMANN, WILLIAM H. (hzawronn. 

